Heat exchanger for air conditioner



March 5, 1968 c. s. BRINDLEY HEAT EXCHANG ER FOR AIR CONDITIONER Filed Oct. 25, 1965 mSDa F mI INVENTOR Claude S. Brindley ATTORNEY United States Patent M 3,371,504 HEAT EXCHANGER FOR AIR CONDITIONER Claude S. Brindley, 254 Freddie Drive, Dallas, TeX. 75217 Filed Oct. 23, 1965, Ser. No. 503,361 1 Claim. (Cl. 62324) This invention relates to an air heating and cooling system, and it has particular reference to certain specific improvements in an air heating and cooling system as hereinafter described which has been extensively used, particularly for heating and cooling small areas, such as individual dwellings.

In one form thereof the invention is applicable to an air heating and cooling system which includes a packaged heat pump consisting of two separate units for use inside and outside a building, respectively, one of said units comprising an evaporator-condenser coil and an air blower and the other of said units comprising a compressor, a condenser-evaporator coil, and a fan, said one of said units ordinarily being located inside a building, and said units having operatively connected between them an expansion valve and valve means for reversing the flow of refrigerant, and a coil arranged in the path of air blown across said evaporator-condenser coil by said blower and connected in a closed system which further includes one or more unit heaters and coolers each having an individual coil through which water is passed and a fan arranged to blow air across said coil, and a series of water distribution pipes having a pump operatively connected therein and arranged to supply hot and chilled water from said first mentioned coil to the respective coils of said unit heaters and coolers.

A heat pump has been defined as a compression type refrigerating system consisting of an evaporator, a condenser, a compressor, and an expansion valve which is so arranged that it cools air in summer and supplies winter heat by pumping heat removed from a low tem- 3,371,504 Patented Mar. 5, 1968 It is well known that when warm, moisture laden air comes in contact with a relatively cooler surface, condensation of the moisture in the air occurs. Condensation of atmospheric moisture often occurs in air heating and cooling systems, which creates a drainage problem as well as being disadvantageous for other reasons. The condensed atmospheric moisture sometimes freezes, and the resulting icing condition may plug air filters and stop the circulation of air through the system, whereby it is inoperable.

In a heating and cooling system as described, condensation of atmospheric moisture may occur in summer as warm, moisture laden atmospheric air comes in contact with the relatively cooler surfaces of the evaporatorcondenser coil, and condensation of atmospheric moisture may occur in winter as warm, moisture laden atmospheric air, which is first heated as it is passed over the evaporator-condenser by the action of the blower, as above described, comes in contact with the relatively cooler surfaces of the coil in the path of said heated air through which cold water is circulated in winter whereby it is heated.

A prime object of the invention is that of providing an air heating and cooling system as described in which the air which is passed over the evaporator-condenser coil by the action of the blower, whereby it is either heated or cooled, as the case may be, and is thereafter passed perature level to a satisfactory higher temperature level. v

This may be accomplished by reversing the flow of refrigerant so that in winter the evaporator becomes the condenser, and vice versa, or alternately, the flow of air may be reversed by means of ducts.

Several well known manufacturers now supply heat pumps, either in the form of separate units for use inside and outside a building, respectively, as described, or as combined units in which the portion thereof which corresponds to the outside unit is connected by ducts to the outside of a building.

The use of heat pumps usually is limited to geographical areas where electricity is readily available at reasonable rates, for the reason that heat pumps are relatively more expensive to operate than other heating and cooling systems, and in areas where the differences between summer and winter temperatures are not great and the Winter temperature is not often lower than about 35 F. Some manufacturers supply small'electrical heating units for auxiliary heating in winter.

During the heating cycle, the refrigerant circulating through a heat pump in reverse direction is heated partly by absorption of heat from the surrounding atmosphere, which is relatively warmer than the cold refrigerant at the moment of evaporation, and partly by compression from the gaseous state to a liquid. Thus the heating of the refrigerant is primarily a result of the electrical energy which is employed to operate the compressor, so that in extremely cold weather it is necessary to operate the compressor substantially all of the time.

The invention is applicable also to air heating and cooling systems as described in which the heating is accomplished independently of the cooling means, by means other than heat pumps, as desired.

over the coil in the path of said air through which water is passed, whereby the water is heated or cooled by indirect heat exchange with the air, is first dehydrated whereby it is substantially moisture free, so that the problem of condensation of atmospheric moisture above referred to is avoided.

A further object of the invention resides in the pro vision of an air heating and cooling system as described which includes an arrangement of air ducts whereby the blower, the evaporator-condenser coil, and the coil in the path of air passed over the evaporator-condenser coil, by the action of the blower, are arranged in a closed system in which substantially dry air is continually recycled from the blower, over the evaporator-condenser coil and said last mentioned coil, and back to the blower.

Broadly, the invention contemplates the provision of a closed system in which substantially dry air is continually recycled from a blower, over heating and cooling means which in one form thereof comprises the evaporator-condenser coil of a heat pump, and a coil in the path of said air through which water is passed, whereby the water is heated or cooled by indirect heat exchange with said air, and back to the blower.

While the foregoing objects are paramount, other and lesser objects will become apparentv as the description proceeds, when considered in connection with the appended drawing wherein:

The single figure illustrated is a flow diagram showing the invention as applied to an arrangement which includes a conventional heat pump, a closed duct system having a water heating and cooling coil, an evaporator-condenser coil and a blower fan housed therein, and a system of water distribution pipes whereby the heated or cooled water is circulated to and from a series of unit heaters and coolers each having an individual coil through which the water is passed and a fan whereby a blast of air is blown over said last mentioned coil.

Referring to the drawing, the numeral 10 designates the evaporator-condenser coil of a conventional heat pump, the numeral 11 indicates the air blower thereof, and the numeral 12 indicates the outside unit of said heat pump, which includes the compressor and the condenser-evaporator.

A water heating and cooling coil 13, which is arranged in the path of a blast of air which is passed over the evaporator-condenser coil by the action of the blower 11, whereby water is adapted to be heated or cooled as it is passed through the coil 13 by indirect heat exchange with said air, is connected in a closed duct system which comprises a series of water distribution pipes 14 having a pump 15 operatively connected therein whereby heated or cooled water from the coil 13 is circulated to and from a series of unit heaters and coolers 16 each having an individual coil 17 through which the heated or cooled water is passed and a fan 18 whereby a blast of air is passed over the coil 17 for heating or cooling an individual room or other area.

The invention comprises an arrangement of air ducts, designated generally by the numeral 19, whereby the blower 11, the evaporator-condenser coil 10, and the water heating and cooling coil 13 are arranged in a closed duct system in which substantially dry air is continually recycled from the blower 11, over the evaporatorcondenser coil 10 and the water heating and cooling coil 13, and back to the blower 11.

The invention contemplates that the air which may be contained in the closed duct system above described initially may be displaced by dry air, or may be dried, or will become dehydrated by condensation and drainage from the system, as desired, after which the same supply of air may be continually recycled while at the same time the introduction of atmospheric moisture to the system is avoided.

The invention may be modified within certain limitations, by persons skilled in the art, without departing from 4 the spirit and intent thereof or the scope of the appended claims.

What is claimed is:

1. In an air heating and cooling system, in combination with a fluid circulation system having connection with a series of heating and cooling units, a duct system closed to outside air and having a blower fan operating therein to circulate air therethrough, an evaporation-condenser coil in said duct system in the path of air circulated therethrough by said fan, a heat transfer coil in said fluid circulation system enclosed in said duct system in the path of air circulated therethrough, a heat pump arranged externally of said duct system having connection with said evaporator-condenser coil whereby to heat or cool the air circulated through said heat transfer coil and whereby said circulated air is dehydrated.

References Cited UNITED STATES PATENTS 1,657,447 1/ 1928 Lindseth 62-406 1,891,231 12/1932 Hull 62-333 1,988,549 1/1935 Gibson 62-333 2,075,225 3/1937 Post 62-99 2,214,055 1/1940 Henney 62333 2,779,171 l/1957 Lindenblad 62-333 3,157,227 11/1964 Palmer -29 3,188,829 6/1965 Siewert 62-160 WILLIAM J. WYE, Primary Examiner. 

1. IN AN AIR HEATING AND COOLING SYSTEM, IN COMBINATION WITH A FLUID CIRCULATION SYSTEM HAVING CONNECTION WITH A SERIES OF HEATING AND COOLING UNITS, A DUCT SYSTEM CLOSED TO OUTSIDE AIR AND HAVING A BLOWER FAN OPERATING THEREIN TO CIRCULATE AIR THERETHROUGH, AN EVAPORATION-CONDENSER COIL IN SAID DUCT SYSTEM IN THE PATH OF AIR CIRCULATED THERETHROUGH BY SAID FAN, A HEAT TRANSFER COIL IN SAID FLUID CIRCULATION SYSTEM ENCLOSED IN SAID DUCT SYSTEM IN THE PATH OF AIR CIRCULATED THERETHROUGH, A HAT PUMP ARRANGED EXTERNALLY OR SAID DUCT SYSTEM HAVING CONNECTION WITH SAID EVAPORATOR-CONDENSER COIL WHEREBY TO HEAT OR COOL THE AIR CIRCULATED THROUGH SAID HEAT TRANSFER COIL AND WHEREBY SAID CIRCULATED AIR IS DEHYDRATED. 